The 8㎜ dia: Sn-38%Pb eutectic alloy rods were produced by use of the horizontal continuous casting process with the heated mold and chill cast process. The cast rods were rolled into 2.0∼0.5㎜ thick plates and structural and mechanical properties were examined. The results revealed that the plates produced by the continuous casting process with the heated mold show much higher superplasticity at ambient temperature (1550% elongation at 0.5㎜ thick plate and 0.5㎜/min strain rate) than the plates procured by chill cast process (630% elongation). Such a high superplasticity of the continuous cast plates is due to the high-quality plates free from any inside and surface defects with fine and uniform distribution of eutectic phases.